class_docstr: Reaction Featurizer.
  
  RxnFeaturizer is a wrapper class for HuggingFace's RobertaTokenizerFast,
  that is intended for featurizing chemical reaction datasets. The featurizer
  computes the source and target required for a seq2seq task and applies the
  RobertaTokenizer on them separately. Additionally, it can also separate or
  mix the reactants and reagents before tokenizing.
  
  Examples
  --------
  >>> from deepchem.feat import RxnFeaturizer
  >>> from transformers import RobertaTokenizerFast
  >>> tokenizer = RobertaTokenizerFast.from_pretrained("seyonec/PubChem10M_SMILES_BPE_450k")
  >>> featurizer = RxnFeaturizer(tokenizer, sep_reagent=True)
  >>> feats = featurizer.featurize(['CCS(=O)(=O)Cl.OCCBr>CCN(CC)CC.CCOCC>CCS(=O)(=O)OCCBr'])
  
  Notes
  -----
  - The featurize method expects a List of reactions.
  - Use the sep_reagent toggle to enable/disable reagent separation.
      - True - Separate the reactants and reagents
      - False - Mix the reactants and reagents
docstr: Handles file name error.
  
  Overrides the __str__ method of the Featurizer base class to avoid errors
  while saving the dataset, due to the large default name of the HuggingFace
  tokenizer.
docstr_tok: ["Handles","file","name","error",".","Overrides","the","__str__","method","of","the","Featurizer","base","class","to","avoid","errors","while","saving","the","dataset",",","due","to","the","large","default","name","of","the","HuggingFace","tokenizer","."]
code: def __str__(self) -> str:
      """Handles file name error.
  
      Overrides the __str__ method of the Featurizer base class to avoid errors
      while saving the dataset, due to the large default name of the HuggingFace
      tokenizer.
      """
      return "RxnFeaturizer_" + str(self.sep_reagent)
  
file_path: deepchem/deepchem/feat/reaction_featurizer.py
imports: from deepchem.feat import Featurizer
  from typing import List
  import numpy
  from numpy.typing import ArrayLike
label_desc: Use image node_id 4 for calling the RxnFeaturizer obj's underlying member method code with example usage: obj.__str__() and returns: unknown